Coupling for reinforced-concrete conduit-sections.



P. S. EASTERDAY. COUPLING FOR REINFORCED CONCRETE CONDUI'I SECTIONS. APPLJIOATION FILED JAN. 27, 1913.

1,061,665." Patented May13,1913.

witnesses UNITED STATE PATENT OFFICE.

PHILIP S. EASTERDAY, 0F PORTLAND, OREGON.

COUPLING FOR REINFORCED-CONCRETE CONDUIT-SECTIONS.

Specification of Letters Yatent. Application flied January 27, 1918. Serial No. 744,564.

Patented May 13, 1913.

To all whom it may concern: I

Be it known that I, PHILIP S. EASTERDAY,

a citizen of the United States, residing at- Portland, in the county of Multnomah and improved construction by which a series of reinforced-concrete conduit sections can be elastically connected together to provide a strong and durable continuous fluid conduit.

A further object of my invention is to provide an improved elastic coupling for rein-- forced-concrete conduit sect-ions, adapted to firmly maintain a tight joint between the abutting conduit ends under all normal conditions, while providing' suflicient elasticity to revent the occurrence of excessive rupturlng strains in the body of theconcrete sections upon settling or shifting of the surrounding earth or other supports.

A further object of my invention is to provide an improved means for elastically connecting a series of-reinforced-concrete conduit sections tightly end to end, adapted to distribute all abnormal strains over sev-.

eral of the adjacent elastic connections; thereby avoiding undue opening of the joint between the abutting ends of said sections and preventing the injurious localization of strains on said concrete sections.

In the accompanying drawings forming a part of this application, and in which similar reference symbols indicate corresponding parts in the several views :-Figure 1 shows two abutting conduit sections of reinforced concrete, with my invention applied thereto; the upper section being shown in vertical section, and the concrete body of the lower section being partly broken away; Fig. 2 is an enlarged detail section on an axial plane of the connected conduit sections, showing the arrangement of my improved elastic coupling; Fig. 3 is a erspective view of one of the connecting r0 s shown in Figs. 1 and 2, with its coils engaging the loop of an adjacent connecting rod; Fig. 4 is a perspective view of my improved elastic locking. pin; Fig. 5 is a erspective view, illustrating a slightly pre erred form of the connecting rod; Fig. 6 is a view similar to Fig. 2, illustrating a modification in which the conduit sections are provided with peripheral rccesses instead of slots; and Fig. 7 is a further modification. 7

Referring to the drawings, 1 and 2 indicate concrete conduit sections reinforced in any suitable manner, as by sheets of expand ed metal'3 embedded therein, and having series of slots 4 in one end thereof.

A series of connecting rods 5 are-embedded in each conduit section and are formed at oneend with a air of axially-spaced coils 6 positioned within said slots 4; the other ends of said rods 5 bein provided with loops 7 projecting beyond t e end of the conduit section for engaging between said coils 6 of an abutting section.

A com ressible elastic locking pin 8 is formed ot a resilient rod wound spirally to provide a coaxial series of coils 9 of tapered, or triangular form, having flat bases 10 and rounded apexes 11; said elastic pin being adapted to be driven, or tightly forced, in the engaged rod coils and loops of the abutting conduit sections for locking the latter together to firmly maintain tight joints between the abutting ends thereof.

In the use of my above described improved construction, the tightly driven elastic spring pins 8 will be further compressed by the engaged rod coils 6 and loops 7 upon strains exerted on the conduit by settlin of the surrounding earth or other causes. uring such compression of the locking pins 8 by abnormal strains, the curvature of the round apexes 11 of the several tapered spring coils thereof will be rapidly shortened, thereby greatly increasing the resistance to compression of said coils; such rapid increase in the resistance to compression causing abnormal strains to be transmitted through the connecting rods 5 and distributed to the elastic couplings of the adjacent concrete sections. This novel action is of great practical advanta e in avoiding undue opening of the joints etween the abut-- ting sections and preventing injurious localization of strains in the latter.

Fi 5 illustrates a preferred form in whic a connecting rod 12 is bent to provide coils 13 and a loop 14 at its respective ends; the free ends of said rod being strongly connected at 15 in any suit-able way.

Fig. 6 illustrates a modification in which one end of each section is provided with peripheral recesses 16 instead of the slots .4

previously described. This provides a construction in which no filling of concrete, or other impervious material, is required in the recesses 16, therebyleaving the interior of the coiled spring locking pins 1 free-'frolri filling.

. Fig. 7 illustratesa modification, in which a connecting rod 16* is bent to provide two coaxial coils 17 at one end'and three coaxial coils 18 at the other end; said two coils being adapted to fit betweenthe three coils ofthe connecting rod of an' adjacent'section, and

'to be locked in position by a key as previously described.

My invention provides a very strong and advantageous construction which can be manufactured at a very low' cost, and which is adapted for use equally well with either round bars, or with any of the patented bars on the market.

I have illustratul and described preferred and satisfactory constructions, but changes could be made within the spirit and scope of my invention.

I claim 1. Ari elastic coupling for reinforced-concrete conduit sections comprising rods pro- 'vided attheirfrespective ends with loops and coils, and a spring pin comprising a coaxial series of tapered coils adapted to be tightly forced within the cooperating rodloops and coils of abutting conduit sections. 2. A reinforced-concrete conduit section provided at one end with peripheral recesses, rods embedded in said concrete section and formed with coils lying within such recesses, loops on said rods projecting from the ends of said concrete section, and spring pins formed of coaxial series of tapered coils adapted to be tightly forced within said rod coils and loops of-abutting conduit sections. In testimony whereof, I afiix my signature, in. presence of two witnesses.

PHILIP S. EASTERDAY. Witnesses:

Eh ANDERSON, ARTHUR P. Tirr'r. 

